1. Field of the Invention
The present invention relates to a digital camera, more particularly to a digital camera which is capable of converting an analog image to a digital image to store it as a static image on a recording medium, and an operator is capable of easily fetching the image to a host computer by connecting the recording medium to the host computer.
2. Description of the Related Art
In general, a digital camera is an input device which converts an analog signal output from a CCD (charged coupled device) to a digital signal and records a static image either in a memory in the camera or in an external recording medium such as a floppy disk and a PCMCIA card, which is a card type memory and a modem card according to standard set by Personal Computer Memory Card Association in United States of America and Japan Electronic Industry Developing Association (JEIDA).
In order to use an image picked up by an ordinary camera in a computer, an object is picked up by the camera. A negative or positive slide is prepared from a photo-graphic film, and an image on the negative or positive slide is printed on a photographic paper. The image on the negative or positive slide or the photographic paper having been printed is scanned by a scanner whereby the image is converted to a digital image. Or, a professional photo studio prepares a photo CD to convert the analog image to the digital image.
The above described treatment requires many steps until the picked-up image actually becomes available in the computer. Particularly, it brings about lack of promptness. For this reason, in a system where data is finally processed by the computer, a digital camera which has an ability to instantaneously form an input image supplied to the computer has been popularized. For example, concerning a news photograph made by a news paper publishing company in which promptness is very important, an image picked up by the digital camera is transmitted to a remote place using a network, thereby increasing its promptness.
Furthermore, instead of image picking-up by a Polaroid camera for damaged portions due to a car accident, the damaged portions are picked-up with a digital camera and the picked-up image can be transmitted to an automobile physical damage insurance company through a network. Furthermore, use of a digital camera has been begun as input means in various kinds of business fields such as confirmations for architecture state by an architectural firm, acquisition of information concerning objects to be dealt with by used car dealers which exchange information through computers, and data input by a realty dealer who performs guides for dealing objects by a computer.
An image written to a recording medium is generally transmitted to a host computer side through various kinds of interface cables, when the recording medium is installed in a camera so that it is impossible to freely detach it from the camera. Furthermore, in case of an external recording medium capable of being freely detached such as a floppy disk and a PCMCIA card, the external recording medium is detached from the camera and it is set to the host computer, whereby the picked-up image is transmitted to the host computer. At this time, when data concerning date and time simultaneously output is stored as a character image superimposed on an original image, the superimposed data is referenced at the time of image display. When the data concerning data and time is separately stored as a text file, the data is displayed on a screen as an image and is referenced with a application software on the host computer.
For the digital camera, a device has been proposed, in which time, comment sentences, or voice information is simultaneously recorded on an output image data for convenience of arranging the data. For example, in Japanese Patent Application Laid Open No. 58-53276, recitations for a technology to record voice information and time information on original image data as well as a technology to record information concerning image picking-up conditions on a file different from an original image data have been made. In Japanese Patent Application Laid Open No. 5-244482, recitations for a technology to enhance facilities for users by superimposing character information on a electronic view finder have been made.
In the conventional digital camera, in case where character information such as image picking-up conditions is superimposed on an initial image forming its compressed image or on an original image, it has been difficult to delete the character information in spite of wish to use the initial image as it is. Furthermore, in case where it is intended to store it as other image picking-up information file, it is necessary to seek a relationship between it and the initial image using some information. An operation for seeking the relationship is performed, for example, by giving the same file name to it as that of the initial image and by giving different accompanying characters to it from those of the initial image. However, in this case, when the number of pieces of the picked-up images increases, the contents of the image can not easily be discriminated only by the file name. Managements for them will be complicated.
Furthermore, when a plurality of images are simultaneously displayed on one screen using a application software on the host computer, a reduced image for use in simultaneous display on one screen (hereinafter, referred to as simultaneous display) is generated by reducing the original image at the time when the simultaneous display function is first selected. After that, the reduced image is used after storing it. No image for use in the simultaneous display is generated within the digital camera. Furthermore, a character synthesis processing is not conducted within the digital camera, and these processings are conducted by the host computer. Therefore, when the simultaneous display is conducted, the host computer is forced to perform excessive processing.